2.0 Analysis 2.1 General The radar controller was aware, at least from ACA870's radio position reports if not from the information contained on the flight progress strip, that this aircraft was what is known as a cutter, and that the flight path of the aircraft would cut across the tracks of other aircraft proceeding eastbound to the ocean. This situation was described as being relatively common for controllers in southern sectors of the Gander airspace. As well, the radar controller communicated with ACA870 one minute and twenty seconds prior to the Pan, Pan, Pan call by the crew. At the time of the communication, the two aircraft were approximately 9nm apart and on a converging course. The radar controller should have detected and resolved the conflict between AFR033 and ACA870 well before the risk of collision occurred. 2.2 Conflict Detection 2.2.1 Information Exchange Some of the factors which actively contributed to the radar controller not detecting the approaching conflict include the following: There was no strip posted at BANCS for ACA870, and there is no provision for the automatic printing of such a strip in the flight progress strip processing software in use in Gander. Notwithstanding the direction in Gander ACC Operations Manual, article 4.1.4, that the sector workplan and the overall strategy shall be determined jointly, there appears to be no procedure which encourages team planning and problem solving. The division of work and the very different work focus of the radar controller and the data controller encourage independent work. This is acknowledged in the Gander ACC Operations Manual, article 4.1.4, where controllers are reminded that It is recognized that during some traffic situations one controller may not be immediately aware of all actions initiated by the other.... The next reminder emphasizing that each controller is responsible for his actions is an accepted philosophy; however, it contributes little to enhancing safety. 2.2.2 Attentive Flight Monitoring The TSB investigations noted in section 1.10.4 bear resemblances to this occurrence in that in each referenced occurrence, the radar controller did not detect aircraft conflicts displayed on the IM. While strip scanning for potential traffic conflicts is necessary, the increasing prevalence of direct off-airway routes, which do not lend themselves to the relatively structured environment for which flight progress strips were designed, puts a premium on the necessity to actively and constantly monitor the IM. While NAV CANADA does provide direction to all controllers on scanning techniques, that subject matter is more oriented to flight progress strip scanning procedures than to definable techniques associated with how to maintain full-time attentive radar flight monitoring. In this occurrence, the radar controller's full-time attentive flight monitoring procedure did not meet the level of attentiveness required to provide an adequate level of safety to the aircraft under his control, and, as a result, the radar controller did not recognize the conflict and did not provide air traffic control radar separation between the two aircraft. 2.2.3 Conflict Resolution Devising a specific separation plan is predicated on recognizing that a situation exists that requires specific action. The benefits of adding specific markings to strips in accordance with articles 2.4 and 8.3.2 of the Gander ACC Operations Manual are restricted to their use as memory aids in that the use of the warnings presupposes that potential conflicts have been recognized. If no conflict is identified, no warning markings are added. Review of the flight progress board for conflicting traffic at common points and full-time attentive flight monitoring of the IM are often the triggering events that enable radar controllers to recognize potential conflicts and to begin the action planning process. Where there is no obvious conflict indicated on the flight progress board (the two aircraft were not posted under a common point and none of the required markings were on either of the flight progress strips), or where the conflict is overlooked during the monitoring process, the radar controller may not devise a specific separation plan and thus may perform no specific separation actions. Where task design does not encourage effective team problem solving, the necessary team planning step may not be accomplished, and the radar controller in his or her tactical control decisions becomes the single, ground-based point of defence against airborne collisions. That defence broke down when the radar controller did not identify the conflict during his monitoring of the tactical situation on the IM. The team supervisor was unable to intervene as a final level of quality control because he was occupied controlling in another sector, and, in any case, his duties preclude detailed knowledge of the control actions of all the controllers in all the sectors of the specialty. There was no procedural or technological defence in the design of this air traffic control process to contain this situation once the radar controller missed the developing conflict. 3.0 Conclusions 3.1 Findings The controllers involved in this occurrence were qualified and current. All equipment available to the controllers was serviceable and being used. Staffing in the sector met unit standards. The supervisor was working in another sector at the time of the occurrence. The workload was assessed as heavy. The radar controller did not devise an active separation action plan because he did not recognize the need for one. The flight progress strips for ACA870 were not marked with the various symbols specified in the Gander ACC Operations Manual indicating that the flight required special attention. The sector controllers' performance of their duties, seemingly in conformance with the directives and the task design in the Gander ACC Operations Manual, did not lend itself to effective sector team problem solving and separation planning, which resulted in the loss of an effective defence. The placement of the two flight progress strips under two separate fixes did not overtly warn the radar controller that the two aircraft at the same altitude would be in close proximity in the vicinity of one of those fixes. There was no rigorous training on radar monitoring methods provided to these controllers in basic air traffic control training or during refresher or specialty training after initial qualification. The TCAS RAs received by the crews of ACA870 and AFR033 provided the only warning and successful resolution to the traffic conflict. Though planned for implementation to meet traffic needs in the early 1990s, a functioning automated conflict alert tool was not available. The Canadian Aviation Safety Board (CASB), the predecessor to the TSB, in 1990, recommended that the air traffic service provider accelerate all initiatives with a potential for providing controllers with automated conflict prediction and alerting. 3.2 Causes The radar controller did not recognize the traffic conflict between ACA870 and AFR033, and, as a result, did not apply the required radar separation criteria between the two aircraft. The fact that the flight progress strip procedures did not provide a flight progress strip for posting at the fix nearest the point of conflict; there was no basic or follow-on training provided to the radar controller in effective radar monitoring techniques; there was no realistic human back-up to the radar controller's activities; and there was no technological back-up in the form of an automated conflict alert tool contributed to this occurrence.